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Lanthanoids
The lanthanide () or lanthanoid () series of chemical elements comprises the 15 metallic chemical elements with atomic numbers 57–71, from lanthanum through lutetium. These elements, along with the chemically similar elements scandium and yttrium, are often collectively known as the rare-earth elements or rare-earth metals. The informal chemical symbol Ln is used in general discussions of lanthanide chemistry to refer to any lanthanide. All but one of the lanthanides are f-block elements, corresponding to the filling of the 4f electron shell. There is some dispute on whether lanthanum or lutetium is a d-block element, but lutetium is usually considered so by those who study the matter; it is included due to its chemical similarities with the other 14. All lanthanide elements form trivalent cations, Ln3+, whose chemistry is largely determined by the ionic radius, which decreases steadily from lanthanum to lutetium. These elements are called lanthanides because the elements in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Periodic Table
The periodic table, also known as the periodic table of the (chemical) elements, is a rows and columns arrangement of the chemical elements. It is widely used in chemistry, physics, and other sciences, and is generally seen as an icon of chemistry. It is a graphic formulation of the periodic law, which states that the properties of the chemical elements exhibit an approximate periodic dependence on their atomic numbers. The table is divided into four roughly rectangular areas called blocks. The rows of the table are called periods, and the columns are called groups. Elements from the same group of the periodic table show similar chemical characteristics. Trends run through the periodic table, with nonmetallic character (keeping their own electrons) increasing from left to right across a period, and from down to up across a group, and metallic character (surrendering electrons to other atoms) increasing in the opposite direction. The underlying reason for these trends is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negative Ion
An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convention. The net charge of an ion is not zero because its total number of electrons is unequal to its total number of protons. A cation is a positively charged ion with fewer electrons than protons while an anion is a negatively charged ion with more electrons than protons. Opposite electric charges are pulled towards one another by electrostatic force, so cations and anions attract each other and readily form ionic compounds. Ions consisting of only a single atom are termed atomic or monatomic ions, while two or more atoms form molecular ions or polyatomic ions. In the case of physical ionization in a fluid (gas or liquid), "ion pairs" are created by spontaneous molecule collisions, where each generated pair consists of a free electron and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandinavia
Scandinavia; Sámi languages: /. ( ) is a subregion#Europe, subregion in Northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. In English usage, ''Scandinavia'' most commonly refers to Denmark, Norway, and Sweden. It can sometimes also refer more narrowly to the Scandinavian Peninsula (which excludes Denmark but includes part of Finland), or more broadly to include all of Finland, Iceland, and the Faroe Islands. The geography of the region is varied, from the Norwegian fjords in the west and Scandinavian mountains covering parts of Norway and Sweden, to the low and flat areas of Denmark in the south, as well as archipelagos and lakes in the east. Most of the population in the region live in the more temperate southern regions, with the northern parts having long, cold, winters. The region became notable during the Viking Age, when Scandinavian peoples participated in large scale raiding, conquest, colonization and trading mostl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ytterby, Sweden
Ytterby () is a village on the Swedish island of Resarö, in Vaxholm Municipality in the Stockholm archipelago. Today the residential area is dominated by suburban homes. The name of the village translates to "outer village". Ytterby is perhaps most famous for being the single richest source of elemental discoveries in the world; the chemical elements yttrium (Y), terbium (Tb), erbium (Er), and ytterbium (Yb) are all named after Ytterby, while four more elements were first discovered there. Mine Quartz was mined in the area beginning in the 1600s for the ironworks in Uppland. Feldspar was mined for local porcelain manufacture, such as Gustavsberg, and the porcelain trade with Britain and Poland. The mine is likely the first feldspar mine in Sweden, starting in 1790. Feldspar mining was likely sporadic and based on manufacture demand. This demand took off in the 1860s, leading to deeper mining efforts at Ytterby. The mine became one of the most productive quartz and feldspar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monazite
Monazite is a primarily reddish-brown phosphate mineral that contains rare-earth elements. Due to variability in composition, monazite is considered a group of minerals. The most common species of the group is monazite-(Ce), that is, the cerium-dominant member of the group. It occurs usually in small isolated crystals. It has a hardness of 5.0 to 5.5 on the Mohs scale of mineral hardness and is relatively dense, about 4.6 to 5.7 g/cm3. There are five different most common species of monazite, depending on the relative amounts of the rare earth elements in the mineral: * monazite-(Ce), ( Ce, La, Nd, Th) PO4 (the most common member), * monazite-(La), (La,Ce,Nd)PO4, * monazite-(Nd), (Nd,La,Ce)PO4, * monazite-(Sm), ( Sm, Gd,Ce,Th)PO4, * monazite-(Pr), ( Pr,Ce,Nd,Th)PO4. The elements in parentheses are listed in the order of their relative proportion within the mineral: lanthanum is the most common rare-earth element in monazite-(La), and so forth. Silica (SiO2) is present in trace a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
